Shape factor

This operation removes peaks that have an aspect ratio greater than a certain value. If the Auto Hough transform is used, the peaks in the Hough space should have an aspect ratio close to unity as special considerations are taken to ensure that most of the peaks are square. This characteristic of the peaks can be used to remove wrongly detected peaks - peaks with an aspect ratio much larger than unity can be eliminated. In short, this operation takes advantage of the proper selection of the Hough transform resolutions and offers the possibility to clean the detected peaks based on their shape.

Parameter

This operation takes one parameter: the threshold value of the aspect ratio. The aspect ratio of the peaks varies between 1 and positive infinity. Typical values for the threshold aspect ratio are therefore between 1.5 and 3, assuming that the peaks should be almost perfectly squared.